NOTE: The current value is compared to the value from the same period in the
previous year to account for seasonality.

Data for the last three years are preliminary.

According to the American Public Transportation Association (APTA), an unlinked
transit trip is a trip on one transit vehicle. A person riding one vehicle from
origin to destination takes one unlinked trip; a person who transfers to a second
vehicle takes two unlinked trips; a person who transfers to a third vehicle takes
three unlinked trips. A linked trip includes all segments on all vehicles used
to travel from origin to destination. APTA estimates that the number of people
riding transit on an average weekday is 45 percent of the number of unlinked transit
passenger trips.

A trendline has been provided for U.S. transit ridership. The trend has been
calculated through a statistical procedure called Structural Modeling, in which
the time series under study is decomposed into seasonal, trend and irregular components.
For further information on this statistical procedure, see: S.J. Koopman, et al.,
Structural Time Series Analyser, Modeller and Predictor (STAMP), London: Timberlake
Consultants Ltd. , 2000